Sayyiduna Abu Sa'id Khudri narrates: Once we were with the Prophet Muhammad (peace be upon him) in a garden belonging to Banu Najjar. At that time, he was riding a mule, which was carrying him along. There were some graves in the garden. The Prophet (peace be upon him) inquired: Who knows about these graves? A man replied: O Messenger of Allah! I do. The Prophet (peace be upon him) asked: Who were they? The man replied: They died upon shirk (polytheism). The Prophet (peace be upon him) said: "If I did not fear that you would stop burying (your dead), I would pray to Allah that He make you hear the punishment of the grave as I have heard it. Surely, this Ummah will be tested in their graves." Then the Prophet (peace be upon him) turned towards us and said: "Seek refuge with Allah from the punishment of Hell and the punishment of the grave, seek refuge with Allah from the apparent and hidden trials, and seek refuge with Allah from the trial of Dajjal."